Nanotechnology at the Core of Columbia’s New Materials Research Center

Columbia University has a new Materials Research Science and Engineering Center (MRSEC), thanks to a National Science Foundation $15 million six-year grant. Under the direction of James Hone, Wang Fong-Jen Professor of Mechanical Engineering, Columbia Engineering, this new center draws upon nanotechnology expertise across the Columbia campus in partnership with City College of New York, Harvard University, Barnard College, Stanford University, and the University of the Virgin Islands. The center comprises two interdisciplinary research groups (IRGs) focused on building higher-dimensional materials from lower-dimensional structures with unprecedented levels of control. Each IRG is targeted at demonstrating the promise of creating novel materials with new functionality and exceptional properties.

Molybdenum disulfide encapsulated between layers of boron nitride

“Our research focuses on basic understanding of how to assemble these nano building blocks into materials and structures, and what properties emerge when we do so. This understanding will ultimately lead to conceptually important and useful new electronic/magnetic devices, optoelectronic systems, and thermoelectric materials,” Hone says. “Both IRGs are built around techniques pioneered by our teams, and bring together researchers with diverse capabilities and a strong record of collaboration.”

The new MRSEC at Columbia, Center for Precision Assembly of Superstratic and Superatomic Solids, or PAS3, is one of 24 across the United States funded by the NSF to support interdisciplinary and multidisciplinary materials research and education of a scope and complexity that would not be feasible under traditional funding of individual research projects.

“This new NSF MRSEC is an important anchor program for Columbia,” Columbia Engineering Dean Mary C. Boyce notes. “Much of my own collaborative research was initiated and/or funded through an NSF MRSEC and I know just how well these programs ignite research, create deep collaborations, and foster a strong sense of community across campuses. This is a significant step for the Engineering School, for Columbia, and all our partners.”

The first IRG, directed by Hone and Lia Krusin, professor of physics at CCNY, will combine two-dimensional (2D) materials into pristine layered heterostructures. Over the past 10 years, Columbia researchers have performed pioneering work in the first such 2D material, graphene—an atomically thin form of carbon. In the past five years, the field has expanded to include a large number of other materials—insulators, semiconductors, metals, and exotic materials such as superconductors. The Columbia team developed techniques to “stack” these diverse materials into layered structures that are atomically perfect—doing on a desktop what could only previously be done using complex high-vacuum apparatus. These heterostructures will enable IRG researchers to investigate and control the properties of 2D materials, understand how they interact in precise ways, and create new interfaces that exhibit emergent electronic phenomena. Importantly, these heterostructures can easily be integrated onto many different platforms: for instance, a system that combines electrical sensing, chemical sensing, and optical imaging can be built on flexible plastic and wrapped around live tissue such as a heart or brain.

“Research on graphene and other 2D atomic crystals is intense and likely to remain one of the hottest topics in condensed matter physics and materials science for many years,” notes Philip Kim, formerly a physics professor at Columbia and now at Harvard, and a partner in the MRSEC. “With steady improvement in fabrication techniques, van der Waals heterostructures promise a new gold rush, rather than a graphene aftershock. This new MRSEC will help us work together to make exciting new discoveries.”

Chemistry Professors Colin Nuckolls, who is the Associate Director of PAS3, and Xiaoyang Zhu will oversee the second IRG. IRG2 researchers will work on creating new materials using precisely defined clusters known as “superatoms” assembled through new forms of inter-cluster chemical bonding. “We can encode properties into the superatom building blocks, and then precisely control how they interact to create materials with tunable properties and multiple functionalities,” Nuckolls explains. IRG2 will develop new superatoms to create a large "periodic table" of designer materials with unprecedented levels of complexity and functionality. It will initially focus on new materials with novel properties useful for magnetic memory; power conversion; and phase transitions that may be induced by optical, mechanical, thermal, and other stimuli.

The new MRSEC will centralize the proposed research and support shared experimental tools at both Columbia and CCNY. Research partners include Brookhaven National Laboratory, IBM, and DuPont, as well as universities and research institutes in Japan, Korea, and Europe.

In addition, the MRSEC will implement a comprehensive education and public outreach program that will improve materials education at many levels. This program will feature multiple programs to introduce materials science to students and teachers at local New York City schools; these will include hands-on demonstrations for elementary school students; a nano-technology course in Columbia’s high school Science Honors Program; summer research programs for high school students and teachers at the Columbia Secondary School for Math, Science and Engineering and at other local schools; and a research training program at LaGuardia Community College. The MRSEC will also provide undergraduate research opportunities, develop new curriculum at the graduate level, and provide career training for students and postdocs.

“Being selected for a MRSEC is a tremendous recognition of our success at Columbia and CCNY in achieving scientific leadership in the cutting-edge areas of layered 2D heterostructures and superatom solids,” Hone adds. “The MRSEC provides crucial research funding to develop fundamental understanding of these new materials and realize their potential for application. Beyond this, the MRSEC will be a home for a vibrant materials research community—by bringing together researchers from many disciplines and backgrounds, we will foster the interactions that will lead to entirely new ideas and research directions. As a center that strongly supports both research and education, our MRSEC will have an enormous impact on this exciting new field of research.”